1. Field of the Invention
The present invention relates to a holding mechanism for an endoscope guide member to hold the endoscope guide member that guides a treatment instrument protruding from a distal end opening portion of an endoscope to a subject, and an endoscope which has this holding mechanism.
2. Description of the Related Art
In general, when a treatment instrument treats a subject such as a bile duct, a side-viewing endoscope and a guide member which guides the treatment instrument to the subject are used.
In this case, the treatment instrument has a cylindrical member through which the guide member can be inserted. The guide member is made of, for example, a thin linear member. The guide member is inserted through the cylindrical member and maintains, for example, the position of a distal end portion of the guide member, thereby the treatment instrument can move along the guide member.
The guide member is inserted, via a treatment instrument insertion hole portion, into a treatment instrument insertion channel which is in communication with the treatment instrument insertion hole portion from a forceps plug portion provided in a grasp portion of the endoscope. The distal end portion of the guide member is then inserted through the treatment instrument insertion channel, and protrudes from the distal end opening portion provided at a distal end portion of the endoscope insertion portion. In the side-viewing endoscope, the distal end portion of the guide member protrudes to a lateral side of the distal end portion of the insertion portion. The distal end portion of the guide member then reaches the subject.
The treatment instrument moves along the guide member by the cylindrical member so that the guide member passes through the guide member. In this instance, the treatment instrument is guided by the guide member, and then inserted into the treatment instrument insertion channel from the forceps plug portion via the treatment instrument insertion hole portion. The treatment instrument is then guided by the guide member, inserted through the treatment instrument insertion channel, protrudes to the lateral side from the distal end opening portion, and reaches the subject. In this way, the treatment instrument is guided to the subject by the guide member.
Such guide members are disclosed in, for example, Jpn. PCT. National Publication No. 2008-529723, Jpn. Pat. Appln. KOKAI Publication No. 2001-340468, and Jpn. PCT. National Publication No. 2001-511023. In Jpn. PCT. National Publication No. 2008-529723, Jpn. Pat. Appln. KOKAI Publication No. 2001-340468, and Jpn. PCT. National Publication No. 2001-511023, a proximal end portion of the guide member is held by a holding member separate from the endoscope so that the guide member is fixed and the displacement of the guide member is prevented. The holding member is attached to the treatment instrument insertion hole portion so that the holding member is attached detachably from the endoscope.